Systems and methods for treatment of obesity and type 2 diabetes

ABSTRACT

The present invention provides systems and methods for treating and controlling obesity and/or type II diabetes. In one aspect of the invention, an internal bypass device includes gastric and duodenal anchors coupled to each other and positioned on either side of the pylorus and a hollow sleeve designed to extend from the pylorus through at least a proximal portion of a patient&#39;s small intestine. The gastric and duodenal anchors are movable between collapsed configurations for advancement through the esophagus and an expanded configuration for inhibiting movement of the anchors through the pyloric sphincter. Thus, the bypass device can be placed and removed endoscopically through the patient&#39;s esophagus in a minimally invasive outpatient procedure and it is “self-anchoring” and does not require invasive tissue fixation within the patient&#39;s GI tract, thereby reducing collateral tissue damage and minimizing its impact on the digestive process.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. Nos. 12/566,131, filed Sep. 24, 2009; 12/566,163 filed Sep. 24,2009; and 12/566,193 filed Sep. 24, 2009; all of which claim the benefitof priority of Provisional Patent Application No. 61/239,506 filed Sep.3, 2009 and all of which are a continuation-in-part of U.S. patentapplication Ser. No. 12/508,701 filed Jul. 24, 2009, which in turnclaims the benefit of priority of Provisional Patent Application No.61/222,206 filed Jul. 1, 2009, the entire disclosures of which arehereby incorporated by reference. This application is also related tocommonly assigned co-pending U.S. Provisional Patent Application No.61/123,472 filed Apr. 9, 2008, U.S. Provisional Patent Application No.61/206,048 filed Jan. 27, 2009, U.S. patent application Ser. No.12/420,219 filed Apr. 8, 2009, U.S. patent application Ser. No.12/384,889 filed Apr. 9, 2009, U.S. patent application Ser. No.12/384,890 filed Apr. 9, 2009 and U.S. patent application Ser. No.12/384,898 filed Apr. 9, 2009; the complete disclosures of which areincorporated herein by reference for all purposes.

BACKGROUND OF THE INVENTION

The present invention relates to the field of obesity and diabetes andmore specifically to minimally invasive systems and methods forcontrolling or treating obesity and/or type 2 diabetes.

Obesity is one of the leading preventable causes of death worldwide andhas become a global epidemic affecting more than 400 million people. Inthe United States alone, approximately 300,000 obesity-linked deathsoccur annually, and obesity-related co-morbities lead to nearly $150billion in healthcare spending. Obesity is a medical conditionassociated with many subsequent diseases, including type-II diabetes,cardiovascular disease, sleep apnea and certain types of cancer. Theseconditions often have severe adverse effects on overall health, reducequality of life, limit productivity, lead to significant medical costs,and can ultimately lead to reduced life expectancy.

While obesity has a range of contributing causes, the vast majority ofobese individuals are obese because they overeat, fail to exerciseadequately, and in some cases have genetic predispositions to weightgain. The primary treatment for obesity is dieting, routine physicalexercise, and in some cases pharmacologic therapy. Obesity surgery,including irreversible Roux-en-Y gastric bypass (RYGB) and LaparoscopicAdjustable Gastric Banding (LAGB), involves surgical restriction of thestomach. These interventions are typically directed at either (i)reducing the caloric intake of the patient by triggering the satietyimpulse more rapidly or physically removing the ability of theindividual to ingest more than a limited amount of food, or (ii)inhibiting the ability of the individual's digestive system to extractthe full caloric value of the food being eaten.

The current surgical treatments for obesity, although often effective inachieving sustainable weight loss and thus reducing associatedco-morbidities, involve gross anatomical reconstruction of the digestivesystem, which may be irreversible. Unfortunately, as has become widelypublicized in the print and broadcast media, there can be significantadverse events, complications, and/or mortality associated with the mostradical of these procedures (including but not limited to RYGB). In alarge number of patients, subsequent surgical procedure(s) are requiredto address the complication(s) from the original surgery. While use ofRYGB and LAGB are approved for individuals with lower BMIs (i.e., <40),the risks associated with the procedures have limited their adoptionand/or use to only the morbidly obese population (>40 BMI). Recentreports indicate that there is a need to expand the options for obesitysurgery in order to provide safer alternatives for individuals who arenot prepared to risk the adverse consequences of radical RYGB and LAGBsurgery, but for whom a surgical intervention is wholly appropriate. Infact, many individuals who could benefit from surgical interventionbefore their excess weight results in serious health problems foregosurgery due to the significant complications and high rates of long-termadverse events leading to poor quality of life. Thus, there is a growingneed for an effective and safe alternative to obesity surgery for theobese patient population worldwide.

Diabetes mellitus type 2 or type 2 diabetes is a disorder that ischaracterized by high blood glucose in the context of insulin resistanceand relative insulin deficiency. There are an estimated 23.6 millionpeople in the U.S. (7.8% of the population) with diabetes with 17.9million being diagnosed, 90% of whom are type 2. With prevalence ratesdoubling between 1990 and 2005, CDC has characterized the increase as anepidemic. Traditionally considered a disease of adults, type 2 diabetesis increasingly diagnosed in children in parallel to rising obesityrates due to alterations in dietary patterns as well as in life stylesduring childhood.

Type 2 diabetes is a chronic, progressive disease that has noestablished cure, but does have well-established treatments which candelay or mitigate the inevitable consequences of the condition. Often,the disease is viewed as progressive since poor management of bloodsugar leads to a myriad of steadily worsening complications. However, ifblood sugar is properly maintained, then the disease is effectivelycured—that is, patients are at no heightened risk for neuropathy,blindness, or any other high blood sugar complication. Type 2 isinitially treated by adjustments in diet and exercise, and by weightloss, most especially in obese patients. The amount of weight loss whichimproves the clinical picture is sometimes modest (2-5 kg or 4.4-11 lb);this is almost certainly due to currently poorly understood aspects offat tissue activity, for instance chemical signaling (especially invisceral fat tissue in and around abdominal organs).

Gastric bypass procedures typically entail surgical restriction of thesize of the stomach and rerouting or bypassing a proximal portion theintestine to reduce absorption of nutrients. A study of 20-years ofgastric bypass patients found that 80% of those with type 2 diabetesbefore surgery no longer required insulin or oral agents to maintainnormal glucose levels. Weight loss also occurred rapidly in many peoplein the study who had had the surgery. Unfortunately, gastric bypassprocedures involve irreversible reconstruction of gastrointestinalanatomy and may be associated with significant adverse events, and/ormortality. In spite of the growth in the number of surgical proceduresfor weight loss (greater than 250,000 annually in the US), only 1.2% ofeligible patients elect to undergo these invasive surgeries each year.

Many patients who could benefit from these procedures forego surgery dueto the significant complications and high rates of long-term adverseevents leading to poor quality of life. The estimated 0.3-2% mortalityrate along with the 19% surgical complication rate for RYGB have beenmajor barriers for expanding the use of surgery in broader patientpopulations.

In view of the foregoing, there is a need in the art for new devices andmethods for controlling and treating obesity and type 2 diabetes.

SUMMARY OF THE INVENTION

The present invention provides systems, apparatus and methods fortreating obesity and/or type 2 diabetes. In one aspect of the invention,an internal bypass device comprises a substantially hollow sleevedesigned to extend from a proximal portion of the duodenum through atleast a portion of the patient's small intestines. The sleeve ispositioned such that partially digested food, i.e. chyme, moving throughthe digestive tract passes through the interior of the sleeve. Thisinhibits the absorption of nutrients/calories in the upper segments ofthe small intestine and delays mixing of chyme with digestive enzymessuch that a quantity of food ingested by the patient will have a smallercaloric value with the sleeve in place.

In addition, several recent clinical studies have demonstrated thatgastric bypass surgical procedures for treating obesity, includingRoux-en-Y, bilio-pancreatic diversion and duodenum exclusion, show arapid and remarkable reduction in clinical symptoms of diabetesincluding normalization of glucose and insulin levels. These effectsoccur before any changes in obesity and suggest that the duodenum maysecrete molecular signals that cause insulin resistance. Supportive datahas also been demonstrated in rat models of diabetes. See, Rubino andMarescaux, Annals of Surgery, 239 No. 1, 1-11 (January 2004), theentirety of which is incorporated herein by reference. Thus, the sleeveis designed to mimic the effects of bypassing the proximal portion ofthe small intestine seen in these surgical procedures. Specifically, itis believed that the sleeve will reduce hormonal triggers that may helpto down-regulate the production of glucose, thereby resulting in anearly immediate relief of Type-II diabetes symptoms. The stabilizationor elimination of Type-II diabetes symptoms will have a beneficialimpact on patient health and further increase weight loss.

In one aspect of the invention, the hollow sleeve includes an anchor atits distal end that fixates the distal end portion of the sleeve at atarget region within the intestines while still maintaining patency ofthe open distal end of the sleeve. This ensures that the sleeve does notmigrate proximally or kink or twist along its length so that chymepassing through the sleeve is not obstructed.

In one embodiment, the anchor comprises one or more projectionsextending from the distal end portion of the sleeve. The projection(s)are configured to engage with a fastening device, such as a clip, clamp,forceps or the like, that may be attached to the distal end of anendoscopic instrument. The fastening device attaches the projection(s)to tissue on the inner walls of the intestines. In an exemplaryembodiment, the fastener is a clip that can be detached from the distalend of its instrument so that the instrument can be withdrawn after thesleeve and clip have been fastened to tissue.

In another embodiment, the anchor comprises a hollow chamber in thedistal end portion of the sleeve. The hollow chamber has a portconfigured for coupling to a fluid delivery system for delivering fluidinto the chamber. This expands the chamber and provides a stable anchorat the distal end portion of the sleeve. In a preferred embodiment, thesleeve comprises one or more internal lumens extending along the lengthof the sleeve and coupling the hollow chamber with the port. Filling theinternal lumens with a fluid, such as saline, can provide furtherstability to the sleeve and inhibit kinking or twisting.

In another aspect of the invention, the internal lumens of the sleevecan be used to deploy the sleeve into its target position within theintestines. A method of deploying the sleeve comprises the steps ofpositioning the sleeve in the proximal duodenum and delivering fluidinto the lumens such that the sleeve extends and “self-deploys” throughthe duodenum.

In an exemplary embodiment, the sleeve is coupled to a pair of anchorsthat reside on either side of the pylorus. The pair of anchors includesa gastric anchor positioned in the pyloric antrum of the stomach coupledto a duodenal anchor positioned in the proximal duodenum. The gastricanchor is movable between a collapsed configuration sized and shaped foradvancement through an esophagus into pyloric antrum and an expandedconfiguration sized and shaped for inhibiting distal movement of thegastric anchor through the pyloric sphincter. The duodenal anchor iscoupled to the hollow sleeve and movable between a collapsedconfiguration sized and shaped for advancement through the esophagus,the stomach and the pyloric sphincter into the proximal duodenum and anexpanded configuration sized and shaped to inhibit proximal movement ofthe duodenal anchor through the pyloric sphincter.

A key advantage of the present invention is that the bypass device canbe placed and removed endoscopically through the patient's esophagus ina minimally invasive outpatient procedure. In addition, the anchorsexpand to fit securely against tissue within the GI tract such that theposition of the device is substantially maintained throughout thedigestive process. Thus, the device is “self-anchoring” and does notrequire invasive tissue fixation within the patient's GI tract, therebyreducing collateral tissue damage and minimizing its impact on thedigestive process. Also, unlike other more invasive procedures such asgastric bypass, the bypass device of the present invention does notrequire any permanent restructuring of the GI anatomy. Once the deviceis removed, the patient's GI tract should begin to function normally andin the same manner as if the device were never placed in the patient.

The gastric and duodenal anchors are preferably coupled to each other byone or more flexible columns that extend through the pyloric sphincter.The flexible columns allow both anchors to move back and forth withinthe stomach and duodenum, respectively, with the natural peristalsismotion of the patient. In the preferred embodiments, the gastric andduodenal anchors will periodically or continuously apply slight contactpressure to the distal portion of the pyloric antrum and the proximalportion of the duodenum, respectively. In an exemplary embodiment, theflexible columns comprise a flexible material that has sufficienttensile strength to withstand the strong peristalsis forces of thepatient, such as silicone or the like.

In another aspect of the invention, a system and method for deliveringan implant, such as the bypass device described above, to a targetregion within the GI tract of a patient is described. The method fordelivering an implant comprises positioning a substantially hollowsleeve within a patient's body such that the sleeve extends through atleast a portion of the duodenum and anchoring the distal end portion ofthe sleeve to a target region in the intestines. Preferably, the sleeveis endoscopically advanced through the pylorus such that it extends fromthe duodenal bulb to the target region between the distal portion of theduodenum to the proximal portion of the jejunum.

In one embodiment, the method includes the steps of engaging a portionof the distal end portion of the sleeve with a fastening device, such asa clip or clamp, and advancing the fastening device and the sleevethrough the patient's GI tract to the target region. Once in position,the fastening device is attached to tissue within the patient'sintestines and detached from the instrument shaft to attach the distalend portion of the sleeve to tissue at the target region.

In another embodiment, the method includes the steps of positioning thesleeve within the proximal duodenum and then delivering a fluid throughone or more internal lumens in the sleeve to allow the sleeve to extendthrough the duodenum and “self-deploy” to the target region.Alternatively, the sleeve may include a mass at its distal endconfigured to allow the sleeve to “self-deploy” through a combination ofgravity and peristalsis.

In an exemplary embodiment, a duodenal anchor coupled to the sleeve isendoscopically advanced through the pylorus into a proximal region ofthe duodenum and then expanded into an operative configuration thatprevents proximal movement of the duodenal anchor through the pyloricsphincter. A gastric anchor coupled to the duodenal anchor is advancedthrough the esophagus into the pyloric antrum of the stomach andexpanded into an operative configuration that prevents distal movementof the gastric anchor through the pyloric sphincter.

Other aspects, features, advantages, etc. will become apparent to oneskilled in the art when the description of the invention herein is takenin conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purposes of illustrating the various aspects of the invention,there are shown in the drawings forms that are presently preferred, itbeing understood, however, that the invention is not limited by or tothe precise data, methodologies, arrangements and instrumentalitiesshown, but rather only by the claims.

FIG. 1 is a view of a portion of a normal GI tract of a human;

FIG. 2 is a perspective view of a bypass device in an operativeconfiguration according to one embodiment of the present invention;

FIG. 3 is a cross-sectional view of a gastric anchor of the bypassdevice of FIG. 2;

FIG. 4 is a top view of an alternative embodiment of a gastric anchoraccording to the present invention;

FIG. 5 illustrates a distal end of a hollow sleeve according to thepresent invention;

FIG. 6 is a cross-sectional view of an alternative embodiment of aduodenal anchor according to the present invention;

FIG. 7 is a top view of the duodenal anchor of FIG. 6;

FIG. 8 is a perspective view of a dissolvable proximal capsule of adelivery system according to the present invention;

FIG. 9 is a perspective view of a dissolvable distal capsule of thedelivery system according to the present invention;

FIG. 10A is a partial cross-sectional view of the bypass device and thedelivery system according to the present invention;

FIG. 10B is a cross-sectional view of a portion of the bypass devicewith fluid tubes of the delivery system still coupled thereto;

FIG. 11 illustrates the insertion of a gastroscope and guidewire throughan esophagus of a patient;

FIG. 12 illustrates the bypass device and a portion of the deliverysystem inserted into the stomach in the esophagus of the patient;

FIG. 13 illustrates the deployment of the duodenal anchor and the sleeveinto the duodenum of the patient;

FIG. 14 illustrates the inflation of the gastric and duodenal anchors;

FIG. 15 illustrates the deployment of the sleeve into the smallintestines of the patient;

FIG. 16 illustrates the bypass device in place in its operativeconfiguration in the patient;

FIG. 17 is a partial cross-sectional view of an alternative embodimentof a valve for the duodenal and gastric anchors of the bypass device;and

FIG. 18 illustrates an alternative introducer tube for the deliverysystem of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the present invention, systems, devices and methods are disclosed fortreating and controlling obesity and/or type II diabetes. In particular,the systems and methods of the present invention provide an internalbypass of a proximal portion of the small intestines to inhibit contactbetween chyme and the bypassed small intestinal walls while allowingnatural peristalsis to occur. The present invention is related tocommonly assigned co-pending patent application Nos. 61/123,472 filedApr. 9, 2008; 61/206,048 filed Jan. 27, 2009; Ser. Nos. 12/420,219 filedApr. 8, 2009; 12/384,889 filed Apr. 9, 2009; 12/384,890 filed Apr. 9,2009 and 12/384,898 filed Apr. 9, 2009, the full disclosures of whichwere previously incorporated herein by reference.

Diabetic foot ulcers are one of the major complications of diabetesmellitus. Foot ulcers occur in 15% of all patients with diabetes andprecede 84% of all lower leg amputations. The significant increase inmortality among diabetic patients with foot ulcers observed over thepast 20 years is considered to be due to the development of macro andmicro vascular complications, including failure of the wound healingprocess.

Wound healing is a ‘make-up’ phenomenon for the portion of tissue thatgets destroyed in any open or closed injury to the skin. Being a naturalphenomenon, wound healing is usually taken care of by the body's innatemechanism of action that works reliably most of the time. The keyfeature of wound healing is the stepwise repair of lost extracellularmatrix (ECM) that forms the largest component of the dermal skin layer.Therefore, controlled and accurate rebuilding becomes essential to avoidunder or over healing that may lead to various abnormalities. But insome cases, certain disorders or physiological insults disturb the woundhealing process that otherwise proceed smoothly in an orderly manner.Diabetes mellitus is one such metabolic disorder that impedes the normalsteps of wound healing process. Many histopathological studies show aprolonged inflammatory phase in diabetic wounds, which causes a delay inthe formation of mature granulation tissue and a parallel reduction inwound tensile strength.

High blood sugar levels prevent white blood cells, which are importantin defending the body against bacteria and also in cleaning up deadtissue and cells, from functioning normally. When these cells do notfunction properly, wounds take much longer to heal and become infectedmore frequently. Also, long-standing diabetes is associated withthickening of blood vessels, which prevents good circulation includingthe delivery of enough oxygen and other nutrients to body tissues.

Another consequence of high blood sugar levels is that the body hasdifficulty producing many important components in the healing process,such as vascular endothelial growth factors (VEGF) and nitric oxide. Forexample, nitric oxide is known as an important stimulator of cellproliferation, maturation and differentiation. Thus, nitric oxideincreases fibroblast proliferation and thereby collagen production inwound healing.

Also, L-arginine and nitric oxide are required for proper cross linkingof collagen fibers, via proline, to minimize scarring and maximize thetensile strength of healed tissue. Endothelial cell specific nitricoxide synthase (EcNOS) is activated by the pulsatile flow of bloodthrough vessels. Nitric oxide produced by EcNOS, maintains the diameterof blood vessels and proper blood flow to tissues. In addition to this,nitric oxide also regulates angiogenesis, which plays a major role inwound healing.

Diabetic patients exhibit reduced ability to generate nitric oxide fromL-arginine. Reasons that have been postulated in the literature includeaccumulation of nitric oxide synthase inhibitor due to high glucoseassociated kidney dysfunction and reduced production of nitric oxidesynthase due to ketoacidosis observed in diabetic patients and pHdependent nature of nitric oxide synthase.

The present invention provides systems, apparatus and methods fortreating wounds in patients, particularly chronic lower limb wounds inpatients lacking the innate ability to regulate glucose (e.g., diabeticpatients). In one aspect of the invention, a method for treating woundsincludes positioning a flexible sleeve within the patient such that thesleeve extends through at least a portion of the duodenum to inhibitcontact between chyme passing therethrough and at least a portion of aninner surface of the duodenum. The hollow sleeve is maintained withinthe duodenum for a sufficient period of time to reduce a blood glucoselevel in the patient. Preferably, the sleeve will be maintained inposition for a sufficient period of time to permit the normalization ofblood glucose levels in the patient (i.e., reducing such glucose levelsto below about 150 mg, preferably below about 125 mg).

The sleeve creates an “internal bypass” that substantially inhibitscontact between chyme and other substances entering the duodenum fromthe stomach of the patient and the bypassed portion of the duodenum.This reduces hormonal triggers that help to down-regulate the productionof glucose, thereby resulting in the relief of certain symptoms thatinhibit the body from effectively healing the wound, such as decreasedperipheral vascular perfusion, neuropathy, a compromised or “inactive”immune system and a reduction in important components of healing, suchas nitric oxide, vascular endothelial growth factors and the like.

In certain embodiments, the sleeve will be maintained in position for asufficient period of time to increase the peripheral vascular perfusionin the patient. Patients lacking the innate ability to regulate glucoselevels often suffer from decreased arterial perfusion of theextremities. The lack of blood flow to the extremities inhibits healingof wounds, such as foot ulcers and the like. In one embodiment of thepresent invention, the flexible sleeve is held in position within theduodenum until this process begins to reverse, thereby increasingperipheral vascular perfusion and allowing for accelerated healing ofthe wound.

In other embodiments, the sleeve will be maintained in position for asufficient period of time to elevate an immune system response in thepatient. Abnormally high glucose levels cause the body's immune systemto become compromised or less active than normal. The white blood cellsor leukocytes of the immune system that defend the body againstinfection become sluggish and unable to effectively fight infections,such as those associated with wounds. In this embodiment, the flexiblesleeve is held in position within the duodenum until the activity ofcirculating leukocytes begins to substantially increase, which allowsthe patient's immune system to do its natural job of fighting theinfection and accelerate healing of the wound.

In other embodiments, the flexible sleeve is maintained in position fora sufficient period of time to increase certain healing factors, such asnitric oxide and vascular endothelial growth factors (VEGF) in thepatient. VEGF is an important signaling protein that stimulates thegrowth of new blood vessels, which can be a critical part of theangiogenesis process in wound healing. In one embodiment of the presentinvention, the flexible sleeve is held in position within the duodenumuntil a sufficient amount of VEGF are produced in the patient toaccelerate healing of the wound.

In other embodiments, the flexible sleeve will be maintained in positionfor a sufficient period of time to halt or reverse neuropathy. Diabeticneuropathy is a common complication of patients lacking the innateability to regulate glucose in which nerves are temporarily orpermanently damaged as a result of high blood sugar levels(hyperglycemia). Neuropathy can complicate the wound healing process,particularly in the extremities. In this embodiment, the sleeve is heldin position until nerves that have not been permanently damaged ordestroyed can be repaired by the body to accelerate healing of thewound.

In a preferred embodiment, the flexible sleeve is sized and shaped toextend from the distal opening of the duodenal anchor through at least aportion of the duodenum (i.e., between about 4-12 inches). In someembodiments, the sleeve may extend throughout the duodenum and into aproximal portion of the jejunum of the patient (i.e., between about12-30 inches, preferably about 12-16 inches). The sleeve issubstantially hollow and positioned such that partially digested food,i.e. chyme, moving through the digestive tract passes through theinterior of the sleeve. This inhibits the absorption ofnutrients/calories in the upper segments of the small intestine anddelays mixing of chyme with digestive enzymes such that a quantity offood ingested by the patient will have a smaller caloric value with thesleeve in place. In addition, it is believed that the sleeve inhibitscertain hormonal triggers that would otherwise occur when food passesthrough the duodenum and proximal jejunum; hormonal triggers that causethe body to become insulin resistant and result in type 2 diabetes.

In certain embodiments, the sleeve is removably introduced through anatural orifice in the patient into the small intestines, preferablyendoscopically through the patient's esophagus, stomach and pylorus. Thesleeve can be maintained in position within the duodenum in a variety ofways known to those of skill in the art (e.g., sutures, hooks, barbs,atraumatic anchoring mechanisms and the like), typically for about 2weeks to one year, preferably between about 1 month to 6 months and morepreferably between about 6-12 weeks.

In a preferred embodiment, the sleeve is maintained in position with apair of anchor elements flexibly coupled to each other and the sleeve.In the preferred embodiment, the flexible anchors are endoscopicallyintroduced with the sleeve and positioned on either side of the pylorus.The duodenal anchor element is preferably expanded to a size that willinhibit proximal movement of the duodenal anchor through the pyloricsphincter to ensure that the sleeve remains in the patient's intestines.Likewise, the gastric anchor element is expanded to a size that willinhibit or prevent distal movement through the pyloric sphincter toensure that the device does not pass further into the intestines andcreate a blockage. In a preferred embodiment, the anchor elements areexpanded by delivering a fluid into each anchor element to inflate saidanchors. In other embodiments, the anchor elements may be expandedmechanically or by other suitable means.

Referring to the drawings, wherein like reference numerals refer to likeelements, there is shown in FIG. 1 an example of a portion of a GI tract10 of a human body. Two smooth muscle valves, or sphincters, contain thecontents of the stomach within the stomach upon ingestion. They are theesophageal sphincter (not shown), found in the cardiac region above theantrum cardiacum, and the pyloric sphincter 20, disposed between thestomach 30 and the small intestine 40. The pylorus 35 is the region ofthe stomach 30 that connects to the duodenum 50. The pylorus 35 isdivided into two parts: the pyloric antrum 60 which connects the body tothe stomach and the pyloric canal which connects to the duodenum 50. Thepyloric sphincter 20 is a strong ring of smooth muscle at the end of thepyloric canal that functions to help regulate the passage of chyme fromstomach 30 to the duodenum 50.

Satiety receptors 80 are generally located all along the inside liningof stomach tissue. Partially undigested food in GI tract 10 is generallyreferred to as chyme. If chyme remains in the region of the stomachbefore flowing into small intestine 40, satiety receptors 80 have agreater chance of being activated, which enhances the ability of anoverweight or obese patient to feel satiated and suppresses the desireto eat.

Pyloric antrum 60 and duodenum 50 are innervated by the enteric nervoussystem and the parasympathetic nervous system (i.e., the vagus nerve).Many researchers have shown that the vagus nerve is responsible for themajority of afferent signals responsible for satiety. Thus, it isbelieved that increasing the afferent vagal nerve activity will resultin satiety signals produced by the brain, making the patient feel morefull and less inclined to eat.

A bypass device according to any of the below-described embodiments ispreferably comprised of a polymeric structure that is compliant andgenerally flexible and bendable. Preferably, at least a portion of thedevice is made of silicone. Some portions of the device may be thickerthan others for enhanced strength properties and to enhance thecapability of the device to resist the natural peristaltic action of GItract 10. Alternatively, some portions of the device may be thinner thanothers to allow for the material peristaltic actions of GI tract 10 tooccur without the device providing a counteractive force. Preferably, ifa portion of the device is bent or twisted during insertion, itspolymeric structure will allow it to revert back to its resting orinitial shape.

The one or more materials that comprise a bypass device according to thepresent invention are preferably selected for their ability to yield andflex during implantation and removal of the device. These propertiesalso protect the patient and the tissues and organs with which thedevice comes into contact. The compliant nature of the bypass deviceallows its configuration to be manipulated during a surgical procedure,preferably in such a way that the device tends to revert to itsoperative configuration. The device may be made of shape memorymaterial, such as nitinol or other known pliable polymeric materials, toallow for expansion back into its operative configuration. Any or all ofthe device may be coated with Teflon to provide a smooth outer surfaceto reduce friction between the device and the patient duringimplantation and removal.

The bypass device according to the present invention is structured toinhibit the rate that chyme passes through GI tract 10, therebyenhancing the ability of chyme to activate satiety receptors 80 andeffectively enhance satiety in a patient. In particular, the device ispreferably structured to reduce the rate of gastric emptying such thatobesity can be controlled by controlling satiety.

The bypass device of the present invention is also designed to provideperiodic or continuous contact pressure on the pyloric antrum and or theproximal portion of the duodenum. This contact pressure modulates(preferably stimulates) one or more nerves within these two structures,thereby increasing their activity. In certain embodiments, this contactpressure is brought about by the design of the device; namely, the flowrestrictor and anchor are coupled to each other by flexible elements orcolumns (discussed in detail below). These flexible columns are sizedsuch that the anchor generally rests against the proximal portion of theduodenum and the flow restrictor generally rests against the distalportion of the pyloric antrum. The flexible columns also have enough“give” or flexibility to allow the anchor and flow restrictor to moveback and forth with the peristaltic motion of the GI tract. Thus, theanchor and flow restrictor may periodically move away from the proximalportion of the duodenum and the distal portion of the pyloric antrum,respectively. However, they will generally move back in contact withthese structures to provide at least periodic pressure contact on thesestructures to stimulate the vagus nerves therein.

The bypass device is also designed to inhibit contact between chymepassing through the duodenum and the inner walls of the duodenum. Thisinhibits the absorption of nutrients/calories in the upper segments ofthe small intestine and delays mixing of chyme with digestive enzymessuch that a quantity of food ingested by the patient will have a smallercaloric value with the sleeve in place. In addition, this reduceshormonal triggers that may help to down-regulate the production ofglucose, thereby resulting in a nearly immediate relief of Type-IIdiabetes symptoms. The stabilization or elimination of Type-II diabetessymptoms will have a beneficial impact on patient health and furtherincrease weight loss.

Incretins are gastrointestinal hormones, produced in response to thetransit of nutrients, that boost insulin production. Because an excessof insulin can determine hypoglycemia (extremely low levels of bloodsugar)—a life-threatening condition, it has been speculated that thebody has a counter-regulatory mechanism (or “anti-incretin” mechanism),activated by the same passage of nutrients through the upper intestine.The latter mechanism would act to decrease both the secretion and theaction of insulin. Thus, in healthy patients, a correct balance betweenincretin and anti-incretin factors maintains normal excursions of sugarlevels in the bloodstream. In some individuals, however, the duodenumand jejunum may be producing too much of this anti-incretin, therebyreducing insulin secretion and blocking the action of insulin,ultimately resulting in Type 2 diabetes.

Indeed, in Type 2 diabetes, cells are resistant to the action of insulin(“insulin resistance”), while the pancreas is unable to produce enoughinsulin to overcome the resistance. After gastrointestinal bypassprocedures, the exclusion of the upper small intestine from the transitof nutrients may offset the abnormal production of anti-incretin,thereby resulting in remission of diabetes. However, it should be notedthat the scientific community has not settled on a particular mechanismof action that causes patients undergoing such bypass procedures to moreless “insulin resistant”. Thus, the present invention is not limited tothis particular mechanism of action or any particular mechanism ofaction.

Certain components of the bypass device according to the presentinvention may be discussed as being attached or connected to oneanother. Preferably, the device is constructed of one continuous pieceand of one material, preferably silicone. However, two or morecomponents of the device may be manufactured separately and subsequentlyassembled. If assembled, components may be glued together using asilicone-based glue.

FIG. 2 illustrates one preferred embodiment of a bypass device 100according to the present invention. As shown, device 100 includes agastric anchor 102 coupled to a duodenal anchor 104 by a plurality offlexible silicone tethers or pyloric columns 106 and a hollow sleeve 108coupled to the distal end of duodenal anchor 104. Pyloric columns 106are designed to extend through the pyloric sphincter 20 to allow bothgastric anchor 102 and duodenal anchor 104 to have some limited movementback and forth within the stomach 30 and duodenum 50, respectively, withthe natural peristalsis motion of the GI tract (see FIG. 16). Pyloriccolumns 106 may be cylindrical or any other type of prismic shape andare preferably designed such that the distance between the distal end ofgastric anchor 102 and the proximal end of duodenal anchor 104 is about10-60 mm, preferably about 20-40 mm, and more preferably about 30 mm, inthe fully extended, but relaxed condition (i.e., non-elasticallyextended). Preferably, device 100 includes at least two, preferablythree, pyloric columns 106 each having a diameter of about 1-5 mm whichare attached to the inside surfaces of anchors 102, 104. Alternatively,anchors 102, 104 may be coupled together with a hollow sleeve thatextends through the pyloric sphincter 20. The sleeve would preferably besufficiently flexible to allow sphincter 20 to open and substantiallyclose without hindrance from the sleeve.

FIG. 3 illustrates a cross-sectional perspective view of an exemplaryembodiment of gastric anchor 102. As shown, gastric anchor 102 includesan internal ring 110 coupled to an annular inflatable membrane 112having a substantially annular or toroidal shape. Inflatable membrane112 comprises an outer wall 114 surrounding a hollow interior 116configured for inflation via a suitable fluid. Ring 110 and membrane 112preferably comprise a flexible biocompatible material, such as aphosphlipid resistant silicone material (e.g., a fluorosiliconecopolymer). Alternatively, ring 110 may comprise a water-absorbentmaterial, such as a hydrogel, that expands and hardens upon contact withfluid. Ring 110 provides structural support for anchor 102, whileinflatable member 112 allows anchor 102 to move between a collapsedconfiguration for introduction through the patient's esophagus and anexpanded configuration within the stomach. Thus, ring 110 is preferablyharder and less flexible than inflatable membrane 112 having a durometerof at least about 70 A, preferably greater than about 80 A, whilemembrane 112 preferably has a durometer between about 30-60 A, morepreferably between about 40-60 A.

In an alternative embodiment, anchor 102 may simply include aninflatable member 112 without support ring 112. In this embodiment, theinflatable member 112 would be inflated to a size and pressuresufficient to withstand peristalsis forces without compressing to a sizethat would allow the anchor 102 to pass through pyloric sphincter 20.

Gastric anchor 102 further includes a fluid inlet 120 for delivery of afluid into hollow interior 116 of membrane 112. In the preferredembodiment, fluid inlet 120 comprises a valve 122 formed along the innercircumference of ring 110 and extending into interior 116 of membrane.As shown, valve 122 includes small chamber 124 in which a hole 126 isformed. Hole 126 extends radially from the inner surface of ring 110,through ring 110, into interior 116 of membrane 112. A flexible siliconeflap 128, formed as part of the interior surface of the inflatablemember 112, is located adjacent to hole 126. Silicone flap 128 serves toocclude hole 126 once the pressure within interior 116 of inflatablemember 112 exceeds the pressure exterior to the member 112, therebyforming a one-way valve to prevent fluid egress from membrane 112.

In addition to, or as an alternative to, the one-way valve, a curablefluid, such as silicone, may be injected into the fluid pathway afterthe saline. The curable fluid will cure and harden, thereby preventingany fluid egress from the interior of inflatable member 112. In anotherembodiment, the inflatable members of the anchors may comprise amaterial that self-seals when punctured with a very sharp smallinstrument such as a syringe. In this embodiment, the inflatable membersof the bypass device may simply be inflated with a syringe and thenself-sealed by the material to prevent fluid egress.

In the preferred embodiment, ring 110 has an inner diameter of about10-50 mm, preferably about 20-40 mm, and more preferably about 30 mm,and a thickness of about 1-5 mm, preferably about 3 mm. Inflatablemembrane 112 has an outer diameter of about 30-70 mm, preferably about40-50, and more preferably about 45 mm, when the pressure withinmembrane 112 is equal to the pressure outside (the state of nominalinflation, i.e., complete inflation without elastic deformation). In thepreferred embodiment, however, membrane 112 is designed such that fluidcan be injected into interior 116 until it has expanded significantlybeyond the initiation of elastic deformation, with a maximum exteriordiameter of the implanted gastric portion preferably being between about50 and 60 mm.

Duodenal anchor 104 preferably has a similar structure as gastric anchor102, including an inner ring 130 and an annular inflatable membrane 132having a substantially annular or toroidal shape (see FIG. 2).Inflatable membrane 132 is designed to inflate into a substantiallyannular shape that provides for a secure anchor against the distalopening of the pyloric sphincter. This ensures that anchor 104 willremain in place within the duodenum 50 despite the natural peristalsisforces acting against anchor 104. Anchor 104 further includes a valvestructure 134 (similar in design to gastric anchor 102) for delivering afluid into an interior of membrane 132 to inflate membrane 132. In theexemplary embodiment, ring 130 has an inner diameter of between about10-20 mm, preferably about 15 mm, a thickness of between about 1-5 mm,preferably about 3 mm. Inflatable membrane 132 preferably has an outerdiameter of between about 20-30 mm, preferably about 25 mm, when thepressure within membrane 132 is equal to the pressure outside (the stateof nominal inflation, i.e., complete inflation without elasticdeformation). Similar to the gastric component, membrane 132 is designedfor inflation beyond the initiation of elastic deformation, with amaximum exterior diameter of the implanted duodenal anchor being betweenabout 30 and 50 mm, preferably between about 35 to 40 mm.

In an alternative embodiment, gastric and duodenal anchors 102, 104include one or more expandable components that either completely orpartially replace the fluid used in the previous embodiment to inflateor expand anchors 102, 104. In a preferred embodiment, the expandablecomponents comprise fluid-absorbent materials designed to expand uponcontact with certain fluid, such as hydrogels. Hydrogels are networks ofpolymer chains that are water-insoluble and hydrophilic. In thisembodiment, a plurality of hydrogel components (not shown) are housedwithin the inflatable members of anchors 102, 104. The hydrogelcomponents will be introduced into the patient in the “dry” or smallerstate within anchors 102, 104. A fluid, such as saline, is deliveredinto the interior of the inflatable members and is absorbed within thehydrogel components (which may be of any shape, such as spheres or thelike) to expand these components, thereby expanding the inflatablemembers.

In one aspect of this embodiment, the anchors 102, 104 include aplurality of hydrogel beads, preferably about 0.5 to 3.0 mm in diameter,designed to expand to a larger size (e.g., about 4-6 mm in diameter)upon hydration with a fluid, such as saline. In this embodiment, anchors102, 104 may or may not include inner rings 110 and they may not requireone-way valves. The hydrogel balls provide additional rigidity to theanchors 102, 104. In addition, they provide additional safety in theevent that the inflatable members are punctured with a small hole as theballs will remain within inflatable members in such event (as opposed toa puncture that will allow all of the fluid to exit inflatable membersin the previous embodiments). Upon removal of the device, the inflatablemembers will be punctured with a large enough hole to allow the hydrogelballs to exit the interiors of the inflatable members. The hydrogelballs can be allowed to pass through the patient's GI tract and excretednaturally.

FIG. 4 illustrates an alternative embodiment of gastric anchor 102. Inthis embodiment, anchor 102 is substantially similar in design andconstruction as the anchor shown in FIG. 2, comprising a central supportring 110 surrounded by an inflatable member 112 having an internal valve120. However, this anchor 102 also includes an internal restrictor plate150 attached to support ring 110. Plate 150 has a central hole 152designed to allow chyme to pass therethrough. Plate 150 serves tosubstantially inhibit the flow of chyme from the stomach to the pyloricsphincter. It is believed that this will cause the prolongation ofsatiety, and result in fewer meals being eaten and/or smaller mealsbeing ingested. The inner diameter of hole 152 will vary depending onthe rate of chyme flow desired for the individual patient. For example,hole 152 may have a diameter of about 5-20 mm.

Referring to FIG. 5, sleeve 108 may be manufactured to any lengthaccording to a particular patient and/or surgical procedure, and in thepreferred embodiment includes at its distal end a beveled tip 109. Alongits length, sleeve 108 may have one or more side holes (not shown) whichprovide further access for chyme to enter sleeve 108. In someembodiments, a rib 131 is disposed along sleeve 108 and is preferablysubstantially parallel to the longitudinal axis of sleeve 108, thoughrib 131 may extend only partially along sleeve 108 and may take on acurved or other type of orientation with respect to the longitudinalaxis. Rib 131 may be comprised of silicone and additionally may includea radiopaque material, such as barium, so that rib 131 may be detectedby a fluoroscope. Rib 131 may be provided as a separate component andlater attached to sleeve 108, or rib 131 may essentially be theoverlapping seam formed during the manufacture of sleeve 108 when a flatpiece of material is rolled into a tubular shape. In such aconfiguration, sleeve 108 may be comprised of a homogenous materialattached by a radiopaque glue. Of course, as rib 131 is primarily usedas an aid during implantation and/or removal of obesity device 100, rib131 need not necessarily be included in this or any other embodimentaccording to the present invention.

Sleeve 108 preferably has a diameter that will substantially correspondwith the inner diameter of the patient's duodenum and a length that willallow the sleeve to extend into at least the proximal portion of thejejunum depending on the individual patient's anatomy. Thus, sleeve 108will typically have a length of between about 20-80 cm, preferablybetween about 55-75 cm, a thickness of about 0.05 mm to 0.22 mm and adiameter of between about 1 to 3 cm, preferably about 2.5 cm.Preferably, the proximal portion of sleeve 108 has an inner diameter ofabout 1.2 cm that expands laterally in the proximal direction to 1.5 cmso that it may be sealed to the lower surface of anchor 104. Thematerial of the sleeve is preferably silicone, such as apolyethylene-reinforced silicone.

Sleeve 108 may include one or more markers (e.g., barium) designed forviewing the position of the sleeve within the intestines throughfluoroscopy, such as rib 131 or other markers that are spaced along thelength of sleeve 108. In addition, sleeve 108 may further includecomponents that inhibit twisting or kinking of the sleeve 108. In oneembodiment, these components include one or more stiffening elements,such as rings, coupled to either the inside or the outside of the sleeveat spaced locations along its length. These rings can, for example, bemade of a slightly thicker silicone material that would resist twistingor kinking of the sleeve around the ring. In other embodiments, thestiffening elements may be in spiral shape or extending lengthwise alongat least a portion of the sleeve 108.

Sleeve 108 may also include one or more internal lumens extending alonga portion of or the entire length of the sleeve. The fluid lumenscomprise a proximal end configured for coupled to a fluid deliverysystem to allow a fluid to flow through sleeve to extend sleeve throughthe patient's duodenum and/or to ensure that sleeve remains patentwithout any twists or kinks along its length. In one embodiment, thesleeve comprises multiple (e.g., 2-5) internal lumens extending from theproximal to the distal end of the sleeve and spaced from each otheraround the circumference of the sleeve. In another embodiment, thesleeve comprises an internal lumen that extends in a spiral pattern downthe length of the sleeve.

In yet another alternative embodiment, sleeve 108 may further includeone or more fluid chamber(s) coupled to one or more of the internallumens. The fluid chamber(s) facilitate implantation of the sleevewithin the patient by allowing the physician to at least partially fillone or more of the chambers before withdrawing the scope from theduodenum (discussed in more detail below). In addition, the fluidchambers provide stiffness to the sleeve to provide more stability tothe sleeve and ensure that it remains in place within the patient afterimplantation. The fluid may also include a material that is observableunder fluoroscopy (e.g., barium or the like) such that the location ofthe internal lumens and/or the fluid chambers can be viewed by aphysician after implantation.

In one embodiment, the fluid chamber comprises an annular passageextending around the circumference of the sleeve at or near its distalend. This configuration provides the additional advantage that, whenfilled, the annular fluid chamber provides a distal anchor for thesleeve and the entire bypass device to provide additional againstproximal migration of the sleeve and/or device. In another embodiment,the sleeve comprises multiple annular fluid chambers spaced along thelength of the sleeve to provide additional rigidity to the sleeve,thereby ensuring that the sleeve remains patent and preventing anykinking or twisting along its length.

In an alternative implantation method, the sleeve 108 may be initiallyfolded “accordion-style” and tucked into the interior of the anchor 104.The distal end of sleeve 108 is initially closed, with a small siliconerubber knob (not shown) attached to the bottom of sleeve 108 (e.g., likea “sock” with a ball on the inside surface of the “toe”). Just proximalto the ball, at a region where the diameter of sleeve 108 is about 2.1cm, is a circumferential perforation (not shown) such that the ball andthe “toe portion” of the sleeve will tear away from sleeve 108 leavingan open tubular sleeve behind.

Referring now to FIGS. 6 and 7, an alternative embodiment of a duodenalanchor 230 will now be described. As shown, anchor 230 comprises anannular support ring 240 coupled to an inflatable flexible membrane 242.In this embodiment, support ring 240 comprises two flat ring elements244 connected together by a semi-rigid central ring 246 that holds theflat ring elements 244 apart from each other. Flat ring elements 244 andcentral ring 246 preferably comprise a suitable material, such assilicone, which may be molded as one-piece or molded separated and gluedtogether with a suitable silicone glue. Flat ring elements 244 arepreferably separated from one another by a distance of about 8-12 mm.Flexible membrane 242 is sealed to the exterior circumferential surfacesof flat ring elements 244 and central ring 246. Membrane 242 isinitially tucked in a space 250 between flat ring elements 244 withsufficient additional material such that when saline is injected intothe interior of membrane 242, an inflated “inner tube” structure iscreated. This inner tube structure is intended to inflate to a maximumdiameter of between 30-45 mm (depending on the specific duodenal anatomyof a given patient).

A one-way valve 252 is disposed between ring elements 244 at onelocation around the circumference thereof and directed inwardly. Thisvalve 252 is initially coupled to a thin tube (not shown) that extendsup along the exterior of the gastric anchor through which membrane 242can be inflated. In an exemplary embodiment, a small wire (not shown) isincorporated into the seal of the inner membrane 242 to the rings topermit simple and rapid deflation of membrane 242 for removal of thedevice. A small ball (not shown) may also be coupled to the wire andlocated external to ring elements 244 and membrane 242 for grasping byan endoscopic instrument. Pulling the ball causes the wire to tearthrough membrane 242 and the seal, thus rupturing membrane 242 andcollapsing anchor 230.

Referring now to FIGS. 8-10B, bypass device 100 further comprises adeployment system 200 for facilitating the deployment of device 100. Asshown in FIGS. 8 and 9, deployment system 200 includes a proximalhousing or capsule 202 and a distal housing or capsule 204. Capsules202, 204 both comprise a biocompatible dissolvable material, such asgelatin and the like, designed to dissolve within the patient's body. Asshown in FIG. 8, distal capsule 204 is sized and shaped to house sleeve108 in a folded, compressed or collapsed configuration and duodenalanchor 104 in its collapsed or deflated configuration (see FIG. 10A).Distal capsule 204 is open at its proximal end, and has a bullet-shapeddistal tip 208 with a small hole 206. Distal tip 208 is designed tofacilitate passage of the capsule 202 (and sleeve 108 and anchor 104therein) through the pylorus and into the duodenum. Hole 206 is sizedand shaped for passage of a guidewire therethrough (see FIGS. 11-15).Capsule 202 is preferably about 80-160 mm long (preferably about 100-140mm long) about 10-30 mm wide (preferably about 20 mm) and is preferablyconstructed to survive for less than 30 minutes before dissolving in thehuman intestines.

As shown in FIG. 9, proximal capsule 202 is sized and shaped to housegastric anchor 102 in its collapsed configuration and at least a portionof columns 106 therein (see FIG. 10A). Proximal capsule 202 issubstantially cylindrically shaped and is primarily designed tofacilitate passage of these components through the esophagus to minimizeany damage to the inner walls of the esophagus. To that end, capsule 204has a slightly curved distal end 205 with an opening 207 that is largerthan distal opening 206 of distal capsule 204 to accommodate the variouscomponents of bypass device 100 therethrough, such as flexible columns106, delivery structure 150 and fluid tube 210 (see FIG. 10B). In thepreferred embodiment, capsule 202 is about 30-70 mm long (preferablyabout 50 mm) and about 10-30 mm wide (preferably about 20 mm). Capsule202 preferably comprises a material that will dissolve in less than 15minutes within the human stomach, such as gelatin and the like.Alternatively, capsules 202, 204 may comprise a resorbable material or amaterial that can be safely excreted by the patient.

Referring now to FIGS. 10A and 10B, deployment system 200 furtherincludes fluid tubes 210, 212 coupled to valves 130, 140 of gastric andduodenal anchors, respectively. Tubes 210, 212 each include smallone-way valves (not shown), such as an umbrella valve or a duckbillvalve, formed in their distal tips. Tubes 210, 212 are preferablycoupled to valves 122, 134 such that their own own-way valves are formedwithin the small chambers 124 of valves 122, 134. Upon inflation of therespective components, the tubes 210, 212 are then cut proximal tovalves 122, 134 such that their one-way valves provide additionalprotection to ensure that fluid injected into the inflatable membranes112, 132 cannot escape through the holes.

Deployment system 200 further comprises a central tube structure 150designed to extend through bypass device 100 (i.e., through the centerof gastric and duodenal anchors 102, 104 and sleeve 108). Central tubestructure 150 has a support tube 152 with an inner lumen 154 sized forpassage of a guidewire therethrough (discussed in detail below). Supporttube 152 has an inner diameter of at least 2.8 mm and preferably about 3mm. Support tube 152 extends through hole 206 in distal capsule 204 andpreferably has widened distal tip 154 designed to engage the outersurface of distal tip 208 of capsule 204. This facilitates passing ofguidewire into the distal opening of support tube 152. Alternatively,support tube 152 may comprise an enlarged distal end (not shown) havinga larger diameter than hole 206 that is located within capsule 204. Inthis embodiment, the enlarged distal end of support tube 152 operates topush against capsule to propel capsule 204 forward as it advancesthrough the patient's GI tract. Support tube 152 preferably comprises amaterial that has sufficient flexibility to easily navigate thepatient's small intestines, yet sufficient rigidity to allow for apushing force from outside of the patient's body to advance tube 152 andthe rest of bypass device 100 through the patient's GI tract (discussedbelow). Suitable materials for support tube 152 are polypropylene andthe like.

Central tube structure 150 further comprises a flexible tube 154extending alongside support tube 150. Flexible tube 154 houses a wire156 coupled to a snare or a clamp 158 at its distal end. An actuator,such as a handle 160 (see FIG. 11), is coupled to the proximal end ofwire 156 for opening and closing clamp 158. As discussed below, flexibletube 154 and clamp 158 are designed to facilitate advancement of sleeve108 through the patient's small intestines to its final deploymentposition. Note that flexible tube 154 and support tube 152 mayalternatively comprise a single tubular structure with two separatelumens (one for wire 156 and one to accommodate the guidewire).

In one embodiment, sleeve 108 comprises one or more small extensions orpolyps (not shown) extending from its distal tip. In this embodiment,tube 154 includes a distal tip (not shown) with a clamp or fastenerdesigned to fasten to the polyps to facilitate advancement of sleeve 108as discussed above. When the sleeve is in its final deployment position,an actuator on handle on the proximal end of the tube 154 allows the useto pull the clamp proximally relative to the distal tip to sever thepolyps and thereby detach tube 154 from the sleeve 108. At this point,central tube structure 150 can be removed from the patient. The polypswill then pass through the patient's GI tract in a normal manner.

In an alternative embodiment, deployment system 200 includes a thin,hollow sheath coupled to a silicone ball (not shown). The ball isdetachably coupled to the distal end of sleeve 108 and the sheathextends through sleeve 108 and duodenal and gastric anchors 102, 104.The ball has an axial hole formed therethrough aligned with the axialbore of the sheath. The axial bore of the flexible sheath has a lengthof about 120 mm, and an outer diameter of about 5 mm. The sheath andball together allow the user to advance sleeve 108 through theintestines to its final deployment position.

In reference to FIGS. 11-16, a method of implanting and removing abypass device 100 according to the present invention will now bedescribed. While the description of this method will be specificallydirected to the embodiments illustrated in FIGS. 2 and 3, it will beunderstood by those skilled in the art that this method (or similarmethods) can be used to implant and remove all of the embodiments of thepresent invention, including embodiments or designs that may not bespecifically described or illustrated herein.

Device 100 enters and exits the patient through esophagus 302 and isultimately positioned in its operative state, wherein pyloric columns106 extend through pyloric sphincter 20 (e.g., see FIG. 15). Initially,a gastroscope 306 is lubricated, inserted into patient's mouth 308, andfed through esophagus 302 and the gastroesophageal (“GE”) junction 310into stomach 320, as shown in FIG. 11. Gastroscope 306 is preferablyapproximately 9.8 millimeters in length, and preferably hasapproximately a 2.8 millimeter working channel and suitable viewing andrecording equipment, for example. It will be understood that tools andcomponents that are described as being passed through or inserted intogastroscope 306 are passed through or inserted into its working channel.A lubricant such as Surgilube or equivalent may be provided as needed tolubricate the bypass device and/or any of the associated surgicalequipment.

Gastroscope 306 should ultimately be positioned such that its distal end308 is adjacent to pyloric sphincter 20. Preferably, a guidewire 322 ishydrated and inserted through gastroscope 306. Guidewire 322 is passedthrough pyloric sphincter 20, which may be aided by manipulation ofgastroscope 306. It may also be beneficial to pass a distal end 308 ofgastroscope 306 through pyloric sphincter 20 in order to maneuverguidewire 322 through same. There should preferably be at least about30-40 centimeters of the length of guidewire 322 passed distally throughpyloric sphincter 20 and into small intestine 40 so that any furthermovement of guidewire 322 during the insertion procedure does not resultin the accidental removal of the distal end of guidewire 322 to aposition proximal of pyloric sphincter 20. Of course, the length ofguidewire 322 that should preferably be passed distally through pyloricsphincter 20 may vary according to different patients and/or proceduresand may be less or more than 30-40 centimeters. After guidewire 322 isappropriately positioned, gastroscope 306 is removed from the patient.

Referring now to FIG. 12, bypass device 100 and delivery system 200 arelubricated and positioned over the guidewire 322 outside of the patientby advancing the proximal end of guidewire 322 through hole 206 indistal capsule 204 and into the inner lumen of support tube 152 (seeFIG. 10). In some embodiments, an overtube (not shown) may be positionedover the guidewire 322 and advanced through the esophagus and into thepatient's stomach. The overtube typically has an inner diameter ofapproximately 16 mm. However, in the preferred embodiment, an overtubeis not required for implantation of bypass device 100. A small steerablescope (not shown) may be advanced through the esophagus into stomach 30through the pylorus and into the proximal portion of the duodenum. Thescope is used to confirm the tissue of the stomach, pylorus and duodenumare robust and show not overt signs that they will not tolerate thedevice. In an exemplary embodiment, a small tube (not shown) may beinserted into the pylorus. The tube includes a distal inner tube-shapedballoon (not shown) that expands to a known diameter with a known volumeof saline. In conjunction with the scope images and other prior imagingdata, this instrument is used to determine the appropriate size ofbypass device 100 to be used, particularly the appropriate size ofduodenal anchor.

Referring now to FIG. 12, once the appropriate size bypass device 100 isselected, distal capsule 204 (containing sleeve 108 and duodenal anchor104) and proximal capsule 202 (containing gastric anchor 102 and atleast a portion of columns 106) are then advanced through the esophagusand into the stomach along guidewire 322. Once through the esophagus,distal and proximal capsules 204, 202 separate, but remain flexiblycoupled together by columns 106 and fluid tube 210 (note that tubes 210,212 are not shown in FIG. 12). The capsules 202, 204 are also stillaligned with each other by virtue of delivery tube structure 150 andguidewire 322 that remain extending through the entire device 100. Oncethe entire device is within the stomach, support tube 152 is used topush the distal end of delivery tube structure 150 and distal capsule204 through the pylorus into the proximal duodenum (see FIG. 13). Thismay require the use of a dilator (not shown) to maintain the pylorus inits maximum diameter. Alternatively, a separate pusher rod (not shown)may be used to push the distal components of bypass device 100 intostomach 30. It should be noted that it may not be necessary toencapsulate any components of device 100 in order to advance themthrough the patient's GI tract. In this case, these components willsimply be advanced in their deflated configurations.

At this point, the surgeon will wait until capsules 202, 204 dissolve(unless capsules 202, 204 are not being used). It is expected thatproximal capsule 202 will dissolve more rapidly, as it is designed to doso, and is subjected to a slightly more caustic environment within thestomach (alternatively, capsules 202, 204 may comprise material that canbe excreted naturally by the patient). Once the proximal components ofbypass device 100 are freed from capsule 202, a fluid, such as saline,is introduced through fluid tube 212 into the interior of inflatablemember 112 until it is filled to the appropriate size (see FIG. 14).After inflating gastric anchor 102, and after distal capsule 204 hasalso dissolved, fluid is delivered through fluid tube 210 into theinterior of inflatable member 132 of duodenal anchor 104 in a similarfashion.

Referring now to FIG. 15, once duodenal anchor 104 has been inflatedinto its operative configuration, sleeve 108 is advanced through theduodenum and into the jejunum to its final deployment position.Specifically, support tube 152 is used to push sleeve 108 and deliverystructure 150 through the patient's small intestines. Once in finalposition, clamp 158 is released via the actuator device or handleoutside of the patient (not shown) to disengage it from the distal endof sleeve 108.

In an alternative embodiment, the surgeon will not wait until distalcapsule 204 is dissolved before advancing sleeve 108 to its finaldeployment position in the small intestines. In this embodiment, oncecapsule 204 has been advanced through the pylorus into the proximalduodenum, gastric anchor 102 is inflated as discussed above. Capsule 204is then advanced further into the duodenum until duodenal anchor 104 isforced out of the proximal opening of capsule 204 (anchor 104 will beprevented from further distal movement by gastric anchor 102). Capsule204 will then be advanced through the duodenum until the distal end ofsleeve 108 reaches its final deployment position. Clamp 158 is thendisengaged from sleeve 108 and removed from the patient as describedabove and capsule 204 will eventually dissolve.

As shown in FIG. 16, bypass device 100 should now be in its finalposition with gastric anchor 102 in pyloric antrum 340 of stomach 30 andduodenal anchor 104 just distal to the pyloric sphincter 20. Deliverystructure 150 is removed from the patient and the distal end of fluidtubes 210, 212 are cut with scissors or the like and removed. Agastroscope and/or fluoroscope (not shown) may be used to confirm thefinal placement of device 100. Once device 100 is in place, guidewire322 can be also removed from the patient.

A method for removing bypass device 100 according to the presentinvention will now be described. A gastroscope may be advanced throughthe esophagus and into the stomach 30 of patient in a suitable positionfor the surgeon to view the procedure. A sharp instrument (not shown)such as scissors or the like, is advanced through the patient'sesophagus into stomach 30. The sharp instrument is used to puncturegastric anchor 102 such that the fluid within the interior of membrane112 exits into the stomach to deflate anchor 102. Alternatively, asyringe or similar suction device (not shown) may be attached to thevalve inlet 120 to withdraw the fluid from gastric anchor 102.

Once deflated, gastric anchor is preferably positioned to the side ofantrum 340. A grasping or cutting instrument (not shown) is advancedthrough the esophagus to cut each of the pyloric columns 106 to detachgastric anchor 102 from the distal portion of device 100. The lastcolumn 106 that is severed will be held by the grasping instrument toensure that duodenal anchor 104 and sleeve 108 do not migrate in thedistal direction after being detached from gastric anchor. At thispoint, a grasping tool or snare (not shown) is advanced into stomach 30to grab gastric anchor 102 and gastric anchor 102 is then pulled throughthe esophagus and removed from the patient.

The sharp cutting instrument is then advanced through the pyloricsphincter 20 to puncture membrane 132 of duodenal anchor 104 to deflateduodenal anchor 104. The grasping instrument may then be used to pullanchor 104 and sleeve 108 into stomach 30. Once duodenal anchor 104 andsleeve 108 are within stomach 30, they may be sliced up and removed orremoved as a single unit. Subsequent to the removal of device 100, ascope (not shown) can be used to determine if any tissue injury orinsult that has been sustained by the implantation, use, or removal ofdevice 100. Provided no additional access to the stomach, pylorus, orduodenum is required, removal of the scope concludes the procedure.

Alternatively, the duodenal anchor 104 can be deflated without severingcolumns 106 and removing gastric anchor 102. In this embodiment, thesharp instrument is advanced around gastric anchor 102, through columns106 and pylorus 20 to duodenal anchor 104. Duodenal anchor is deflatedand pulled into the stomach (along with sleeve 108). The entire bypassdevice 100 may then be removed as a single unit, or it may be sliced upinto smaller components to facilitate passage through the patient'sesophagus.

FIG. 17 illustrates one portion of an alternative embodiment of thegastric and duodenal anchors (for convenience only one of the anchors isshown in FIG. 17). In this embodiment, the anchors both include an outerwall housing a hollow interior designed for inflation as describedabove. FIG. 17 illustrates a central portion 400 of the outer wall ofthe anchors. As shown, the anchors further include a valve 402 having aninlet 404, a one-way valve member 406, a fluid passage 408 and anexpandable member 410 located within fluid passage 408 between theinterior of the anchor and valve member 406. Expandable member 410preferably comprises a material designed to slowly absorb fluid upon,such as water or saline and expand with the absorbed fluid. In thepreferred embodiment, expandable member 440 comprises a hydrogelmaterial although other materials can be used that are well known in theart.

To inflate the anchor, fluid is delivered through inlet 404 such that itpasses via fluid passage 408 past expandable member 410 and valve member406 into the interior of the anchor. Valve member 406 is designed toprevent the fluid from flowing back through fluid passage 408 and inlet404. As additional protection from this event occurring, however,expandable member 410 will absorb fluid as the fluid fills the interiorof the anchor and passes back through passage 408 to saturate expandablemember 410. Expandable member 410 is designed to expand when hydratedsuch that it completely blocks fluid passage 408, thereby preventing anyfluid flow in either direction through fluid passage. This not onlyprovides additional protection from fluid leakage, but also prevents anyunwanted fluid (such as stomach acid and the like) from passing into theinterior of the anchor.

FIG. 18 illustrates an alternative embodiment of a delivery system 450of the present invention. In this embodiment, system 450 comprises anintroducer tube 451 defining an elongate shaft 452 that has sufficientflexibility to extend through a patient's esophagus into the stomach(similar to the overtube described above). Shaft 452 has an open distalend 454 and an open proximal end (not shown as the entire shaft 452 oftube 451 is not shown in FIG. 18) and an internal lumen 458 designed asa working channel for passing instruments therethrough. Tube 451 furthercomprises a thin flexible bag or sleeve 460 comprising a suitablebiocompatible material such as silicone or the like. Sleeve 460 houses abypass device 462 such as one of the bypass devices described above.Sleeve 460 is preferably long enough to extend entirely through internallumen 458 of shaft 452 to facilitate placement of sleeve 460 and device462 in tube 451 (see below). In the preferred embodiment, sleeve 460 hasopen distal and proximal ends and is fastened to the proximal end ofintroducer tube 451 such that sleeve 460 remains within tube 451 whendevice 462 is propelled from tube 451 (see below). Sleeve 460 is alsosized to allow it to fit within internal lumen 458 while still housingbypass device 462 in its collapsed configuration.

System 450 may optionally include a pusher or advancing member 464including an elongate rod 465 with a proximal handle (not shown) and adistal pusher 466 designed to press against a proximal end of bypassdevice 462 when bypass device 462 is loaded within lumen 458 of tube451. In some embodiments, handle 467 can be used to collapse or expandpusher 466 (discussed below). Tube 451 further comprises a tapereddistal end 459 around distal opening 454 to provide for atraumaticadvancement through the esophagus.

In use, bypass device 462 is placed within sleeve 460 and sleeve 460 isloaded into the distal end portion of internal lumen 458. In a preferredembodiment, the user extends the proximal end of sleeve 460 through theentire length of lumen 458 and pulls sleeve 460 proximally such thatbypass device 462 is pulled into the distal end portion of lumen 458.Once loaded, the device 462 is ready for implantation in the patient.

To implant the device, introducer tube 451 is extended through thepatient's esophagus such that its proximal opening 454 is positionedwithin the stomach. Bypass device 462 is then propelled out of tube 451into the stomach. This can be accomplished by passing advancing member464 through proximal opening 456 of introducer tube 451 and advancing itthrough lumen 458 until it propels bypass device 462 out of the distalopening 454 of tube 451. Alternatively, other devices, such as agastroscope, can be used to propel bypass device into the stomach.

In the preferred embodiment, sleeve 460 has open proximal and distalends and is designed to remain within lumen 458 of tube 451 as bypassdevice 462 is advanced into the stomach. Thus, both sleeve 462 and tube451 can be easily removed from the patient after device 462 has beendeployed. In other embodiments, sleeve 462 passes into the stomach alongwith device 462 and is then detached or removed from device 462. Thiscan be accomplished by a variety of means, such as cutting the sleeveaway from the device 462. Alternatively, sleeve 462 may already includea cut-a-way portion that can be easily detached to open sleeve 462 andallow bypass device 462 to be removed. In yet another embodiment, sleeve462 may comprise a dissolvable material that dissolves away within thestomach (similar to the capsules discussed above). Once it has beendeployed into the stomach, bypass device 462 may be passed along aguidewire and deployed into its final position as discussed above.

In certain embodiments, introducer tube 451 is long enough to extendthrough the esophagus and stomach and through the pylorus into theduodenum of the patient. In these embodiments, tube 451 may optionallyinclude a bend at its distal end portion to facilitate passage of thetube 451 through the natural bend in the human stomach between theesophagus and the pylorus. Alternatively, the delivery system mayinclude a separate overtube having such a bend. In this embodiment, theseparate overtube will be first inserted through the esophagus with aseparate straight introducer therein (i.e., to maintain the overtube ina substantially straight configuration as it passes through theesophagus). Once the overtube has passed through the esophagus, thestraight introducer is removed such that the overtube is allowed to bendwithin the stomach into its natural position. At that point, theflexible introducer tube 451 housing the bypass device is advancedthrough the overtube to the duodenum.

In use, once the distal opening of tube 451 resides in the duodenum, thedistal end portions (i.e., the sleeve and the duodenal anchor) of thebypass device are propelled out of the distal opening of the introducertube 451 and into the duodenum of the patient. The duodenal anchor isthen inflated to prevent proximal movement of the distal end portions ofthe bypass device. The introducer tube 451 is then retracted through thepylorus and into the stomach. As this occurs, the gastric anchor willnaturally be pulled out of the distal end of the introducer tube 451from the counterforce of the inflated duodenal anchor against the distalsurface of the pylorus. The gastric anchor may then be inflated withinthe stomach and the sleeve extended through the duodenum as describedabove.

In yet another alternative embodiment, the pusher device or advancingmember is designed to perform multiple functions. Namely, the pusherdevice is sized and shaped to fit between the gastric and duodenalanchors within the introducer tube. In this capacity, the pusher deviceis used to push or propel duodenal anchor and sleeve out of the distalopening of the introducer tube into the duodenum. In addition, thepusher device will function to prevent the gastric anchor from beingadvanced through such distal opening when the distal opening is locatedwithin the duodenum. Once the distal opening of the introducer tube hasbeen retracted through the pylorus into the stomach, the pusher deviceis designed to collapse and retract proximally through the middle of thegastric anchor. It can then be expanded again to propel the gastricanchor through the distal opening of the introducer tube and into thepatient's stomach.

In one embodiment, the pusher device comprises an elongate rod coupledto a umbrella-shaped or claw-shaped proximal pushing device. The rod issized to extend through the introducer tube and through the center ofthe gastric anchor. The proximal pushing device is sized to residebetween the gastric and duodenal anchors. Distal advancement of the rodwill cause the pusher device to propel the duodenal anchor through thedistal opening of the introducer tube. The pusher device furthercomprises an actuator at the proximal end of the rod for collapsing theumbrella-shaped pushing device such that it can be retracted proximallythrough the center of the gastric anchor. The actuator can then be usedto expand the pushing device such that further distal advancement of therod will cause the pusher device to propel the gastric anchor throughthe distal opening in the introducer tube.

In yet another embodiment, an alternative method for implanting andremoving the bypass devices of the present invention is now described.In this embodiment, the hollow sleeve includes one or more projectionsat its distal end designed to allow an endoscopic forceps, clips, clampor similar device to attach to the projections. The projections can beloops, strings, protuberances or the like and are preferably made of thesame material as the sleeve (such as silicone). The gastric and/orduodenal anchors may also include such projections for similar purposes.

In use, the bypass device is attached to an endoscopic scope by passingan endoscopic forceps or clamping device through the working channel ofthe scope and attaching the forceps to the projections on the distal endof the sleeve. The physician may then attach the remainder of the bypassdevice to the outer surface of the scope with a shroud, sleeve or otherfastening device or just simply align the bypass device with the shaftof the scope. Alternatively, the scope may be advanced through thecenter of the two anchors of the bypass device and the sleeve such thatthe entire bypass device is positioned around the scope. The scope isadvanced with the distal end of the sleeve through the patient'sesophagus and stomach and through the pylorus into the duodenum. Theremainder of the sleeve and the anchors of the bypass device are therebypulled into the stomach alongside the scope.

Alternatively, the physician may attach the forceps to the projectionson either the gastric or duodenal anchor and advance those portions ofthe implant through the esophagus first (i.e., passing the device intothe stomach backwards). In this embodiment, the physician may thendetach the forceps from the bypass device, remove the scope and attachthe forceps to the distal end of the sleeve to advance the remainder ofthe sleeve into the patient's stomach. To avoid retraction of theanchors back through the esophagus, the gastric anchor may be fully orpartially inflated after the forceps have been detached from the anchorand before withdrawing the scope through the esophagus.

After the anchors have been advanced into the stomach of the patient,the gastric anchor is preferably either partially or fully inflated asdescribed above to prevent movement of the gastric anchor through thepylorus into the duodenum or through the lower esophageal sphincter intothe esophagus. The physician then continues to advance the scope and thedistal end of the sleeve through the duodenum to a position near thefinal target site within the patient's intestines (either in the distalduodenum or the proximal jejunum). At this point, the physician maydetach the forceps from the distal end of the sleeve and withdraw thescope and forceps back into the patient's stomach.

To prevent the sleeve from “following” the scope proximally into thestomach, the physician will preferably temporarily fixate the sleevewithin the duodenum. According to the present invention, one method oftemporarily fixating the sleeve is to use a detachable clip (rather thanthe forceps described above) to grab the projection on the distal end ofthe sleeve. Once in position within the duodenum, the clip is opened andattached to mucosal tissue within the duodenum. The clip can then bedeployed such that it is no longer attached to its shaft, but insteadfastens the sleeve to the mucosal tissue on the inner wall of theintestines. This allows the scope and shaft of the clip device to bewithdrawn while the sleeve is fixated within the duodenum.

In certain embodiments, multiple clips may be used to fasten the sleeveto the inner walls of the intestines. The clips may serve the purpose ofcreating an additional anchor for the device to prevent migration and toensure that the sleeve remains patent during the period of time it isimplanted within the patient. In addition, the clips will preferably beobservable under fluoroscopy such that the physician can ensure that thesleeve has remained in place after implantation.

In another embodiment, the sleeve comprises one or more internal lumensextending down a portion of, or the entire length of, the sleeve. Theinternal lumens are preferably fluidly coupled to one of the flexiblecolumns which are, in turn, fluidly coupled to a valve within thegastric anchor. In an exemplary embodiment, the sleeve will comprise 3or 4 internal lumens spaced around its circumference. In use, a fluid isdelivered through the gastric anchor and column and into the internallumens of the sleeve. The fluid causes the sleeve to extend fully andinhibits proximal migration of the sleeve when the scope is retractedfrom the patient's duodenum. In addition, the fluid-filled lumens willensure that the sleeve remains patent without any kinks or twists alongits length.

Once the scope has been retracted from the duodenum, the duodenal anchoris advanced past the patient's pylorus into the proximal portion of theduodenum. Preferably, the scope is used to push the duodenal anchorthrough the pylorus. Alternatively, the forceps can be attached to oneof the projections on either of the gastric or duodenal anchors to pushand/or pull the duodenal anchor into position. The duodenal anchor isthen inflated as described above.

In yet another alternative embodiment, the sleeve is “self-deploying”through the duodenum. In this embodiment, the sleeve is positionedwithin the proximal duodenum as described above and then allowed to“self-deploy” and advance through the duodenum into position. In oneembodiment, the sleeve comprises internal fluid lumens as describedabove and the fluid is delivered into the lumens to force the sleeve toextend down the length of the duodenum. In another embodiment, thesleeve comprises a mass at its distal end (e.g., a thickened annularportion of the sleeve, one or more balls or projections attached to thedistal end or the like). The mass will advance through the patient'sintestines through natural peristalsis and pull the sleeve distallyuntil it is fully extended. In yet another embodiment, the sleevecomprises a dissolvable portion at its distal end that occludes all or aportion of the distal end of the sleeve. In this embodiment, fluid isflushed through the sleeve and because its distal end is occluded causesthe sleeve to extend distally. After the dissolvable portion dissolveswithin the intestines, the distal end of the sleeve is opened up toallow chyme to pass therethrough.

Although the invention herein has been described with reference toparticular embodiments, it is to be understood that these embodimentsare merely illustrative of the principles and applications of thepresent invention. It is therefore to be understood that numerousmodifications may be made to the illustrative embodiments and that otherarrangements may be devised without departing from the spirit and scopeof the present invention as defined by the appended claims.

1. A device for treating obesity and/or type II diabetes in a patientcomprising a substantially hollow sleeve having open proximal and distalends and an internal lumen therebetween having a proximal end configuredfor coupled to a fluid delivery source, the sleeve being sized andshaped to extend through at least a proximal portion of a duodenum ofthe patient.
 2. The device of claim 1 wherein the sleeve furthercomprises a fluid chamber in close proximity to the open distal end andin fluid communication with the internal lumen.
 3. The device of claim 2wherein the fluid chamber is a substantially annular passage at thedistal end of the sleeve.
 4. The device of claim 1 further comprising aplurality of internal lumens extending along a length of the sleeve andspaced from each other around a circumference of the sleeve.
 5. Thedevice of claim 1 wherein the internal lumen extends in a substantiallyspiral pattern along a length of the sleeve.
 6. The device of claim 1wherein the sleeve further comprises multiple fluid chambers between theopen proximal and distal ends, the fluid chambers fluidly coupled to theinternal lumen.
 7. The device of claim 1 further comprising an anchorcoupled to the proximal end of the sleeve and movable between acollapsed configuration sized and shaped for advancement through anesophagus into a selected region of a stomach of the patient and anexpanded configuration sized and shaped for substantially inhibitingmovement of the hollow sleeve.
 8. The device of claim 7 wherein theanchor is sized and shaped in the collapsed configuration to advancethrough a pylorus and into the duodenum of the patient and wherein theanchor is sized and shaped in the expanded configuration tosubstantially inhibit proximal movement of the anchor back through thepylorus.
 9. The device of claim 8 wherein the anchor is a first anchor,the device further comprising a second anchor coupled to the firstanchor and being movable between a collapsed configuration sized andshaped for advancement through an esophagus into a selected region of astomach of the patient and an expanded configuration sized and shapedfor substantially inhibiting distal movement of the second anchorthrough the pylorus.
 10. The device of claim 1 wherein the hollow sleeveis sized and shaped to extend from a proximal portion of the duodenuminto a jejunum of the patient.
 11. A method for deploying an implantwithin a target region in a GI tract of a patient comprising:introducing a substantially hollow sleeve through an esophagus andstomach of a patient and into a duodenum; anchoring a proximal portionof the sleeve within a proximal region of the duodenum; and delivering afluid into a portion of the sleeve to extend the sleeve through at leasta portion of the duodenum.
 12. The method of claim 11 wherein theanchoring step comprises inflating an anchor member coupled to theproximal end of the sleeve.
 13. The method of claim 11 whereindelivering step is carried out by delivering fluid through an internallumen extending at least a portion of the length of the sleeve.
 14. Themethod of claim 11 further comprising the step of anchoring a distal endportion of the hollow sleeve within a target region in the intestines.15. The method of claim 14 wherein the anchoring step is carried out bydelivering fluid to a hollow chamber in the distal end portion of thesleeve.
 16. The method of claim 11 wherein the introducing step iscarried out by coupling the sleeve to a scope and advancing the scopethrough the patient's esophagus and stomach and into the duodenum. 17.The method of claim 16 wherein the coupling step is carried out byextending an instrument through a working channel of the scope andfastening a distal end portion of the instrument to the sleeve.
 18. Amethod of positioning a substantially hollow sleeve into the GI tract ofa patient comprising: introducing the sleeve through an esophagus andstomach of a patient and into a target region within a small intestinesof the patient; and anchoring a distal end portion of the sleeve totissue at the target region.
 19. The method of claim 18 wherein theanchoring step comprises fastening the distal end portion of the sleeveto tissue at the target region.
 20. The method of claim 18 wherein theanchoring step comprises delivering a fluid to a chamber within thedistal end portion of the sleeve.
 21. The method of claim 19 wherein thefastening step is carried out by engaging a clip to a projection on thedistal end portion of the sleeve and attaching the clip to tissue on theinner wall of the intestines.
 22. The method of claim 21 wherein theclip is at a distal end of an instrument and the introducing step iscarried out by advancing the clip and the distal end portion of thesleeve therewith through the esophagus and stomach into the intestinesof the patient.
 23. The method of claim 22 further comprisingdisengaging the clip from the instrument after the clip has beenattached to the tissue and withdrawing the instrument from the patient.24. The method of claim 18 further comprising anchoring a proximal endportion of the sleeve to a region within the proximal duodenum of thepatient.
 25. A device for treating obesity and/or type II diabetes in apatient comprising a substantially hollow sleeve having open proximaland distal end portions and an anchor at the distal end portion forfixing the distal end portion in a target region of an intestines of thepatient, the sleeve being sized and shaped to extend through at least aproximal portion of a duodenum of the patient.
 26. The device of claim25 wherein the anchor comprises a projection extending from the distalend portion of the sleeve and sized and shaped for engaging a fasteningdevice to fasten the projection to tissue within the intestines of thepatient.
 27. The device of claim 26 wherein the projection comprises aloop extending outward from a distal end of the hollow sleeve.
 28. Thedevice of claim 26 wherein the projection comprises one or more stringsextending outward from a distal end portion of the hollow sleeve. 29.The device of claim 25 wherein the anchor comprises a hollow chamber inthe distal end portion of the sleeve, the hollow chamber having aproximal opening configured for coupling to a fluid delivery tube. 30.The device of claim 29 wherein the sleeve further comprises an internalfluid passage fluidly coupled to the hollow chamber and extending alonga length of the sleeve, and wherein the internal fluid passage comprisesa proximal opening configured for coupling to the fluid delivery tube.